This document summarizes a workshop on using new technologies to understand and change health behaviors. It provides two examples of how continuous digital data can provide insights: daily self-weighing data over a year showed patterns in weight variability that associated with weight management success; analysis of heart rate variability data from over 14,000 individuals revealed novel patterns in physical activity levels by weekday and month. The document concludes that data from modern wearables can help develop dynamic computational models of behavior to support health behavior change and maintenance.